import ctypes
path = r'E:\01_Lab\VisualStudioLab\cpp_dll\cpp_dll\Debug\cpp_dll.dll'
dll = ctypes.WinDLL(path)
 
dll.add_float.argtypes = [ctypes.c_float,ctypes.c_float]
dll.add_float.restype = ctypes.c_float
 
data_float = dll.add_float(7,10) # (ctypes.c_float(7.0),ctypes.c_float(10.0))

DLLEXPORT float __stdcall add_float(float a,float b)
{
 float sum = a + b;
 return sum;
}